Abstract schema name

In the ejb-jar.xml, entity beans can have a abstract-schema-name tag, which specifies the name used in "from" clauses of the EJB-QL of finder and select methods. In practice, this tag is usually just set to be the same as ejb-name. Is there any reason to use a different value? In other words, is there even any reason to have an abstract-schema-name tag as part of the spec?